What hazardous conditions are commonly associated with thunderstorms?

Thunderstorms are known for their severe and varied weather phenomena that pose significant risks to aviation. The correct answer highlights several hazardous conditions typically associated with thunderstorms, including hazardous turbulence, hail, poor visibility, and lightning.

Hazardous turbulence arises from the intense updrafts and downdrafts present in and around thunderstorms, making for unpredictable and dangerous flying conditions. Hail can form within these storms as strong updrafts carry water droplets high into the atmosphere where they freeze and create ice pellets that can damage aircraft upon impact. Poor visibility often accompanies thunderstorms, primarily due to heavy rain, which can significantly reduce a pilot's ability to see the runway or other critical navigation points. Lightning is another common characteristic of thunderstorms, posing risks not only to the aircraft but also to ground operations and personnel.

In contrast, the other options describe conditions that are not typically associated with thunderstorms. Low temperatures and high visibility are unlikely when a thunderstorm is present. Stable air and calm conditions are generally indicative of fair weather, which is the opposite of what occurs during a thunderstorm. Clear skies and moderate temperatures are also contradictory to the very nature of thunderstorms, which tend to develop in unstable atmospheric conditions and often lead to overcast or stormy weather.